2nd Gen Neon 2000 - 2005 2nd Gen Neon

knocking noise at idle.

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Old 11-12-2011, 06:35 PM
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Default knocking noise at idle.

Hello all. I have an 03 neon sxt. It Makes a ticking/knocking noise from motor at idle. Some mechanic guy told me have i recently checked my oil. I always check my oil before turning on my car. I use royar purple motor oil. Any ideas on the noise???? Thanks...
 
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Old 11-13-2011, 05:03 AM
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Originally Posted by DiabloSxt
Hello all. I have an 03 neon sxt. It Makes a ticking/knocking noise from motor at idle. Some mechanic guy told me have i recently checked my oil. I always check my oil before turning on my car. I use royar purple motor oil. Any ideas on the noise???? Thanks...

Does it get more or less noticable when you raise RPMS? Like say 3000-5000?
 
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Old 11-13-2011, 12:27 PM
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Originally Posted by chew*
Does it get more or less noticable when you raise RPMS? Like say 3000-5000?
No it goes away. Some say it normal for a neon with 52,000 miles. I doubt it tho. Its only wile it idles.
 
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Old 11-13-2011, 07:18 PM
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Originally Posted by DiabloSxt
No it goes away. Some say it normal for a neon with 52,000 miles. I doubt it tho. Its only wile it idles.
Only at idle is normal. Probably pistn slap.

I have an engine with 90k here I am taking apart. I will snap some pics of the piston skirts to show whats happening.
 
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Old 11-13-2011, 10:59 PM
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Chew:

Depends on how bad the lifter(s) is/are that's causing the noise. I just pulled a rocker that was making racket throughout the RPM range because it's damaged enough that it won't pump up at all. That's the problem I'm dealing with now....it makes noise constantly, and is so bad it's causing a loss of power and a slight miss at idle.

If by piston slap you mean that the piston or cylinder is so worn that the piston is jacking sideways in the cylinder, then it's unlikely unless he's also burning very large amounts of oil.

If it's not a lifter/rocker (which is FAR more likely), then the odds are it's probably a wrist pin or connecting rod. The lifters in these things are so horribly ****-poor made that I'm surprised the factory didn't do a recall and replace all of them 10 years ago. I'm working on a mechanical lash adjuster conversion on mine now, and will post pics and procedures if it works like I hope it does.
 
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Old 11-14-2011, 12:48 AM
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The piston slap is due ito tolerances, alum piston and a steel block and is a known issue in neon's most noticeable when cold. The bottome end of part of skirt can hit near the bottom of cylinder and you would loose no oil

You only hear it at idle or very low rpm. My current engine does it and has been for a while. It's also been drag launched at 3500 and revved to 8000+ more times than i can count, i'd think by now I would have nuked the engine if it was lifters or lower end, but nope I just keep blowing trannies...........

A lifter will increase with rpm as well as a wrist pin and can be heard through entire rpm range which is why that was my first question.

Since this is not through entire rpm range it's most likely not a lifter or wrist pin.

As far as your issue which I already read your thread, just install a rocker assembly from a pt cruiser, problem solved.

I've revved the stock rockers/lifters out to 8k+ many times with no issues, chances are the car you got was just not maintained well.
 

Last edited by chew*; 11-14-2011 at 12:54 AM.
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Old 11-14-2011, 04:18 AM
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Originally Posted by chew*
The piston slap is due ito tolerances, alum piston and a steel block and is a known issue in neon's most noticeable when cold. The bottome end of part of skirt can hit near the bottom of cylinder and you would loose no oil

You only hear it at idle or very low rpm. My current engine does it and has been for a while. It's also been drag launched at 3500 and revved to 8000+ more times than i can count, i'd think by now I would have nuked the engine if it was lifters or lower end, but nope I just keep blowing trannies...........

A lifter will increase with rpm as well as a wrist pin and can be heard through entire rpm range which is why that was my first question.

Since this is not through entire rpm range it's most likely not a lifter or wrist pin.

As far as your issue which I already read your thread, just install a rocker assembly from a pt cruiser, problem solved.

I've revved the stock rockers/lifters out to 8k+ many times with no issues, chances are the car you got was just not maintained well.
A little more info here, if you would, please...what year PT cruiser, what motor, would the rocker assembly be interchangeable with this 2.0 SOHC??

Also...lifter racket is often unpredictable, it all depends on what's wrong with the lifter itself, whether it makes more racket at lower RPM, higher, whatever, at least in my experience with other vehicles. A lifter that isn't sealing internally like it should might make alot of noise at idle, but quiet completely when the RPM comes up high enough to outrun the excess bleed-off.

A wrist pin will often make much more noise on deceleration. One of the ways to help diagnose a wrist pin problem is to pull the plug wire from the suspected cylinder while it's idling, and if it's the wrist pin it'll usually make at least a little more noise.
 
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Old 11-14-2011, 10:44 AM
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Up to I believe 2006 pt cruiser, any 2.0 engine. I haven't verified if the 2.4 turbo is interchangeable yet.

Also if you take the valve springs off a PT it's considered an upgrade and able to handle say a crane 14 cam...
 
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Old 11-14-2011, 11:02 AM
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I don't even see a PT cruiser built with a 2.0, all I see listed are 2.4 or other.

Also, the valvetrains on the 2.0 and 2.4 are entirely different, the 2.4 has rockers that individually bolt to the head, the 2.0 rockers are shaft mounted.

Also...I'm not after any hot-rod here, I'm just interested in having this thing run normally, with little or no racket. If I want a hot-rod, it's going to be a V-8 in something that is better looking than a 2000 Neon.
 
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Old 11-14-2011, 11:13 AM
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After a little more research, the only 2.0 in a PT cruiser I can find is in a non-US version. Most of the others came with a 2.4, or 2.2, from what I can see. No valve-train parts look to be interchangeable at all.
 

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